Plastics and elastomers are polymers. Another polymer to consider is polyurethanes. I assist in the engineering, operation and production of pre-polymer systems. Which is very interesting I must say. We react diisocyanates and polyols to form these systems.
Urethane elastomers are made from prepolymers and curatives and there physical properties are the result of their components.
ex.- polyols make up the soft segment, and isocyanates and curatives make up the hard segment.